Generators of gas turbine engines are used for up and down regulation and electrical capacity generation. However, these systems have characteristics where power increase or decrease can happen over several minutes. In order to maintain the stability of the electric grid, a major concern is the unexpected and sudden loss of electricity generation which will cause a frequency drop on the grid. Currently, the best source of fast acting regulation to support this drop condition is hydro power, or power generated from a water source, because hydro can act in seconds and can maintain the desired output. However, relying on hydro power is geographically limited and as the grid grows, a dis-proportionate low level of new hydro generation is being added due to environmental constraints.
Gas turbine engines can also be used in support of this drop condition, but are not nearly as effective as hydro because they require a ramp rate to the desired load conditions which takes minutes, not seconds. Furthermore, in order to have this generating capacity available, the gas turbine engine must be online and at a power level below base load, which is a less efficient set point to operate a gas turbine.